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Python Python Basics (Retired) Putting the "Fun" Back in "Function" Functions

Make a function named add_list that takes a list. The function should then add all of the items in the list together

Make a function named add_list that takes a list. The function should then add all of the items in the list together and return the total. Assume the list contains only numbers. You'll probably want to use a for loop. You will not need to use input().

functions.py
# add_list([1, 2, 3]) should return 6
# summarize([1, 2, 3]) should return "The sum of [1, 2, 3] is 6."
# Note: both functions will only take *one* argument each.

2 Answers

Tony McCabe
Tony McCabe
4,889 Points

def add_list(sum): result = 5 for i in sum: result += i return result Luckly, I know a little Python, but here is what passed...

William Li
PLUS
William Li
Courses Plus Student 26,865 Points

If must use loop, then the code is sth like this

def add_list(li):
    result = 0
    for i in li:
        result += i
    return result

There's more concise way of writing this function if you aren't required to use loop

def add_list(li):
    return sum(li)
Kenneth Love
Kenneth Love
Treehouse Guest Teacher

Even more concise: add_list = sum.

I don't actually care if you use a list here or not, but it's good practice to do it the long way.

How do you know this? It was never mentioned in the Videos... or am I doing something wrong?